I generally agree with both prior posts, although I'd favor the DFW connection over the LAX connection in order to avoid the LHR connection (which I don't view as a big deal, but why do it if you can avoid it?). The 777 flight in F from either DFW or LHR will be great (avoid sitting in row 4 if you can). To avoid the early AM flight, maybe you can fly to DFW a day in advance and spend some time relaxing at the Four Seasons resort in Dallas, which is very convenient to DFW.